Upper limb prostheses, a type of Assistive Technology (AT), aim to restore compromised functions or enhance capabilities, supporting the daily life of individuals with disabilities. In this context, 3D printing can be an innovative solution that reduces costs and waiting times associated with acquiring this AT, as well as facilitating customizations that can meet individual needs and preferences. Thus, this paper presents the development of a low-cost myoelectric prosthesis for upper limbs using rapid prototyping, aimed at the Brazilian scenario. A three-step methodological process was followed: selecting a reference project, reverse engineering, and prototype development. Partial results were obtained in three areas: electrical signals, motor action, and cost analysis. This ongoing work reinforces the feasibility of significantly reducing costs and production times for upper limb prostheses using 3D printing, enhancing the Brazilian AT market; it also aligns with the Sustainable Development Goals, exploring innovation in developing this type of AT with a focus on inclusion and accessibility.